Orientation Programming For 4-Axis Kinematics; Orientation Programming For 5-Axis Kinematics - Siemens SINUMERIK 840D sl Function Manual

13.6.2

Orientation programming for 4-axis kinematics

Tool orientation for 4-axis kinematic
4-axis kinematics possess only one degree of freedom for orientation. When the orientation is
programmed using RPY angles, Euler angles or direction vectors, it is not generally possible
to guarantee that the specified orientation can be approached. If used at all, this type of
orientation programming is only suitable for certain types of kinematic, i.e. those which
feature an invariance in orientation angles relative to the basic axes. This is the case for the
SCARA kinematic, for example.
For this reason, orientation programming is only permitted via "orientation angle" A for 4-axis
kinematics. This angle corresponds to the RPY angle C according to the robotics definition,
i.e. one rotation about the Z-RO axis, as illustrated in Fig. "Orientation angle for 4-axis
kinematic".
Figure 13-28 Orientation angle for 4-axis kinematic
13.6.3

Orientation programming for 5-axis kinematics

Tool orientation for 5-axis kinematics
For 5-axis kinematics, when programming via orientation vector, it is assumed that the
orientation vector corresponds to the x component of the tool.
When programming via orientation angle (RPY angle according to robotics definition), the x
component of the tool is considered as the initial point for rotations.
For this purpose, the vector in the x tool direction, as shown in Fig. "Orientation angle for 5-
axis kinematic", is first rotated around the Z axis by the angle A and then around the rotated Y
axis by the angle B. The rotation by the angle C is not possible for 5-axis kinematics because
of the restricted degrees of freedom for the orientation.
Special Functions
Function Manual, 09/2011, 6FC5397-2BP40-2BA0
TE4: Transformation package handling
13.6 Tool orientation
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